1. Field of the Invention
The present invention relates to a rail vehicle comprising a wagon body and a suspension system with a running gear supporting the wagon body. The present invention further relates to a method for detecting malfunction in a suspension system of such a rail vehicle.
2. Description of Related Art
In modem rail vehicles it is generally known to detect malfunctions within the suspension system of the rail vehicle which have an adverse effect on the running stability of the rail vehicle. Typically, vibration sensors or the like are used to capture actual values of status variables representative of the accelerations acting on specific component of the suspension system of a vehicle. The data obtained in this way are then analyzed in order to detect situations with excessive accelerations acting within the suspension system which are representative of a malfunction of the suspension system. If such a malfunction situation is detected, corresponding malfunction warning signals are issued in order to initiate appropriate countermeasures to avoid hazardous situations. Such systems are for example known from WO 01/81147 A1.
However, during operation of a rail vehicle unacceptable and potentially hazardous situations may not only result from an inappropriate vibrational behavior of the running gear of the vehicle. For example, excess lateral movements of the wagon body with respect to the running gear may lead to a violation of the kinematic envelope defined for the specific track the vehicle is negotiating. In order to avoid such violations of the kinematic envelope under any circumstances, typically, the outer contour of the wagon body and the suspension system of a rail vehicle are specifically adapted to the track system the vehicle is to be operated on.
Although, by this means, in a passive suspension system a violation of the kinematic envelope of the respective track may be effectively avoided, this approach has the disadvantage that it typically results, on the one hand, in a rather restricted outer contour of the wagon body which reduces the transport capacity of the vehicle and, on the other hand, in a rather rigid suspension of the wagon body which is undesirable in terms of passenger comfort.
A further problem exists for active suspension systems comprising, for example, and active tilt control of the wagon body with respect to the running gear (i.e. a control of the tilting angle or the rolling angle, respectively, of the wagon body about a tilting axis or rolling axis, respectively, extending along the longitudinal direction of the wagon body). In such systems, for example, a malfunction of the tilting control system may lead to the introduction of excessive excursions on the wagon body with respect to the running gear leading to violations of the kinematic envelope. The same applies to an active sway motion control of the wagon body.
A further problem that may arise with such active suspension systems is that, for example, a malfunction of the tilting control system may lead to the introduction of opposite lateral excursions of the wagon body with respect to the leading running gear and the trailing running gear. Such a situation, due to the specific kinematics of such a tilting system, would lead to a torsional loading of the wagon body leading to undesired unloading of some of the wheels of the running gears and, consequently, to a considerable increase in the risk of derailment.
It is thus an object of the present invention to provide a rail vehicle as outlined above that, at least to some extent, overcomes the above disadvantages. It is a further object of the present invention to provide a rail vehicle that provides both, high transport capacity as well as high passenger comfort while ensuring safe and reliable operation under any circumstances. Finally, it is an object of the present invention to provide a method for detecting malfunction in a suspension system allowing realization of such a vehicle.